8: This limit is of the type ∞ − ∞. Since the expression involves polynomials and roots, one could try to use the methods from the box "polynomials and sums with powers", that is, factor out the dominant term.

One could also try to use the method from the box "difference of roots": get rid of the roots algebraically. However, since the two terms do not have the same dominant, removing the square roots does not result in any substantial simplification. The first approach is much superior.

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